1. Field of the Invention
The present invention relates generally to an electrical connector, and more particularly to an improvement in an electrical connector which has a housing, in which a flat circuit device, such as a flexible printed circuit board (hereinafter, referred to as an FPC) or a flexible flat cable assembly (hereinafter, referred to as an FFC) is inserted, a plurality of conductive contacts arranged in the housing for coming into contact with connecting terminals provided on the flat circuit device inserted in the housing, so as to put the connecting terminals provided on the flat circuit device in electrical connection with a solid circuit board, and locking means for engaging with the flat circuit device inserted in the housing so as to hold the same to be prevented from getting out of the housing unwillingly.
2. Description of the Prior Art
A flat circuit device, such as a relatively small-sized FPC or FFC, used in electronic apparatus of various kinds is often connected electrically with a solid circuit board, on which various electrical parts are directly mounted, with an electrical connector which is fixed to and connected electrically with the solid circuit board. The electrical connector has a plurality of conductive contacts, an end portion of each of which is connected electrically with a conductive circuit pattern portion formed on the solid circuit board and which are provided for coming into contact with connecting terminals provided on the flat circuit device, and is operative to cause each of the connecting terminals provided on the flat circuit board to be electrically connected through the conductive contact with the conductive circuit pattern portion formed on the solid circuit board.
A previously proposed electrical connector thus used for connecting electrically a flat circuit device, such as an FPC, with a solid circuit board, is provided with a housing made of insulator, which is mounted on the solid circuit board and has an opening through which at least a part of the flat circuit device is inserted into the housing. In the housing, a plurality of conductive contacts are provided to be arranged along the opening and connected electrically with circuit terminals provided on the solid circuit board. These conductive contacts are operative to come into contact respectively with a plurality of connecting terminals provided on the flat circuit device when the flat circuit device is inserted into the housing through the opening provided thereon. With the conductive contacts of the electrical connector put in a condition for coming into contact with the connecting terminals on the flat circuit device, the flat circuit device is electrically connected with the solid circuit board.
The electrical connectors, each of which has the housing, in which the flat circuit device is inserted, are divided broadly into two types, one of which is the horizontal insertion type wherein the flat circuit device is inserted in the housing through the opening provided thereon along a direction substantially parallel to the solid circuit board on which the housing is mounted and the other of which is the vertical insertion type wherein the flat circuit device is inserted in the housing through the opening provided thereon along a direction substantially perpendicular to the solid circuit board on which the housing is mounted. The housing of each of the electrical connectors has a mounting outer surface portion which faces closely or comes into contact with the solid circuit board when the housing is mounted on the solid circuit board. In the electrical connector of the horizontal insertion type, the housing has the opening which is so provided that the flat circuit device is inserted in the housing through the opening along a direction substantially parallel to the mounting outer surface portion of the housing, and in the electrical connector of the vertical insertion type, the housing has the opening which is so provided that the flat circuit device is inserted in the housing through the opening along a direction substantially perpendicular to the mounting outer surface portion of the housing.
In the previously proposed electrical connector of either the horizontal insertion type or the vertical insertion type, when the flat circuit device is inserted in the housing through the opening provided thereon and the conductive contacts provided in the housing are put in press-contact with the connecting terminals provided on the flat circuit device so that the flat circuit device is put in electrical connection with the solid circuit board on which the housing is mounted, it is required to prevent the flat circuit device inserted in the housing from getting out of the housing unwillingly. It is a matter of course that it is necessary for the flat circuit device inserted in the housing to be held stably so as not to get out of the housing unwillingly in order to keep the conductive contacts provided in the housing properly in a condition of press-contact with the connecting terminals provided on the flat circuit device.
Accordingly, regarding the electrical connectors of the vertical insertion type, there has been also proposed previously an electrical connector which is provided with a locking means for engaging with the flat circuit device inserted in the housing through the opening provided thereon along a direction perpendicular to the solid circuit board on which the housing is fixed so as to hold the same to be prevented from getting out of the housing unwillingly, as shown in, for example, the Japanese patent application published before examination under publication number 2001-196130 (hereinafter, referred to as published patent document 1).
In the electrical connector (a connector with a locking mechanism for an FPC/FFC) shown in the published patent document 1, a housing (an insulator 10) mounted on a solid circuit board (a board B) is provided with an opening (11) extending in a direction (a vertical direction) perpendicular to the solid circuit board, and a flat circuit device (a FPC/FFC 20) is inserted in the housing through the opening (11) along the direction perpendicular to the solid circuit board. Further, the housing is provided with a pair of locking means (locking levers 15) at both end portions thereof in its longitudinal direction. Each of the locking means is put on an axis (14) to be rotatable and has a horizontal portion (15a) operative to take a posture for extending to be parallel to the solid circuit board when any external force, such as pressure, does not act thereon and a slanted portion (15b) operative to take a posture for inclining to the solid circuit board when the external force, such as the pressure, does not act thereon. The horizontal portion (15a) and the slanted portion (15b) of the locking means are arranged to be rotatable in a body on the axis (14).
A top end of the slanted portion (15b) of the locking means is put in the opening (11) provided on the housing when any external force, such as pressure, does not act on the slanted portion (15b) of the locking means. Therefore, when the flat circuit device is inserted in the housing through the opening (11) provided thereon, first the slanted portion (15b) of the locking means is pushed by one of projections (22) provided on an end portion of the flat circuit device and thereby the locking means in its entirety is rotated in such a manner that the top end of the slanted portion (15b) of the locking means is pushed out of the opening (11).
Then, when the flat circuit device is further inserted in the housing so that the end portion of the flat circuit device reaches a predetermined correct position in the housing, the projection (22) provided on the end portion of the flat circuit device has passed a position corresponding to the top end of the slanted portion (15b) of the locking means and therefore the slanted portion (15b) of the locking means is released from a condition wherein the slanted portion (15b) of the locking means is pushed by the projection (22) of the flat circuit device. Accordingly, the locking means rotates to restore to the original state in such a manner that the top end of the slanted portion (15b) of the locking means is put in the opening (11) provided on the housing so that the horizontal portion (15a) of the locking means is caused to take the posture for extending to be parallel to the solid circuit board on which the housing is fixed and the slanted portion (15b) of the locking means is caused to take the posture for inclining to the solid circuit board.
Under the above-mentioned condition wherein the flat circuit device has been inserted in the housing through the opening (11) provided thereon, the top end of the slanted portion (15b) of the locking means, which is put in the opening (11), is caused to engage with a step portion (23) formed by the projection (22) of the flat circuit device. As a result, each of the locking means is operative to cause the top end of the slanted portions (15b) to engage with the step portion (23) formed by the projection (22) of the flat circuit device for holding the flat circuit device so as to prevent the same from getting out of the housing unwillingly when undesirable external force acts on the flat circuit device for drawing the same out of the housing.
In the electrical connector of the vertical insertion type thus proposed previously, which is provided with the locking means operative to prevent the flat circuit device inserted in the housing from getting out of the housing unwillingly, each of the locking levers (15) constituting the locking means is provided to be rotatable to the housing as an independent member separated from the housing and rotated in response to the inserting of the flat circuit device in the housing. Further, when occasion demands, a rib member for enforcing resiliently the locking lever (15) is also provided on the housing to ensure the rotation of the locking lever (15) in response to the inserting of the flat circuit device in the housing.
Accordingly, in the case of the above-mentioned previously proposed electrical connector of the vertical insertion type, there have been disadvantages that the number of constitutive parts of the electrical connector increases undesirably, a working process for assembling the electrical connector is undesirably complicated and a production cost of the electrical connector rises disagreeably.